They were 'cowed' into silence by threats. [=they did not complain, publicly say anything, etc., because they had been threatened]
They'll be arguing about this 'till the cows come home'.
The football team was a 'cash cow' for the university.
(..) - Yeah, I can. - No, you can't. - Yes, I can. - No, you can't. I'm telling you, no one can. See? That's all I ever do. You almost have this side. Holy cow. - You almost had that one. - I'm gonna get it. Look at that. You're almost there. - This is me. Good job. - Goodbye. - Yeah. I'll see you soon. (..)2006 The Pursuit of Happyness